There are many electronic devices capable of generating data which needs to be printed in document form. This general class of document generators includes such devices as computers, facsimile machines, digital cameras and copiers, medical imaging devices, optical scanners, satellite imaging devices, scientific data collection devices, etc. It is common among these types of devices to employ a single processor to perform the various data collection, organization and print request functions. Unfortunately, when the processor is busy processing a print request it is unavailable for other tasks.
One example which readily demonstrates this problem is when the user of a personal computer requests multiple copies of a single document and then has to wait until the computer completes multiple print requests before he or she can again use the computer. To help combat this problem, computer application designers developed background printing which attempts to make the computer more available by processing print requests printing only during idle times for the processor. In this instance, a multipage collated document printed "n" number of times would significantly slow down foreground processing of the user's document. This implementation is a consequence of the way the command "copies=" was originally implemented on Hewlett-Packard Company LaserJet.RTM. printers, specifically in the printer command language (PCL), which has become an industry standard. Most users experience a noticeable decrease in the response of the computer. Additionally, when the print job is sent repeatedly over a computer network to the printer, the response time of the communications network can be noticeably affected.
Printing multiple copies of a multipage, collated document using a software application, such as a word processor, involves multiple transmissions to the printer from the application. In DOS environments, the user can suffer a significant loss of productivity due to the time taken by the application to format and print multiple jobs. Since the printer command "copies=" is page-based, not print job based, drivers were unable to provide collated multiple copies. Clever coding allowed applications to loop as many times as the number of copies. As the job consisted of back to back repeated collated pages, customers received a collated job despite the "copies=" limitations. While the coding may be clever, this still wastes network bandwidth, and in some cases, causes the print job to be processed at a rate which is significantly slower than the theoretical speed of the print engine.
These problems associated with of requesting multiple copies of a printed job were largely solved through the introduction of Hewlett-Packard's Mopier.RTM. printers. The operational features of the Mopier.RTM., which are described in U.S. Pat. No. 5,764,863 entitled Multiple Original Copy Data Printer incorporated herein by reference, provide a way to print multiple copies from a single transmission of only one copy of the document to decrease the use of network resources, computing time and storage space necessary for printing multiple copies or "mopies."
Conventional printers and even Mopiers, however, have heretofore not been capable of providing a variety of advanced print job control features enabled in part by the Mopier's ability to generate multiple copies at the printer. For example, it may be desirable to store print jobs indefinitely for future printing of additional copies. This feature could be particularly helpful in printing environments where forms and other graphically intense documents are generated repeatedly. It may also be desirable to allow a user to secure privacy when printing confidential documents by allowing the user to send a confidential document to the printer but have the printer delay printing the document until the user authorizes printing by entering a privacy code at the printer.